Waste liquid treating apparatus

ABSTRACT

A waste liquid treating apparatus includes a waste liquid accommodating unit for waste water discharged from a processing apparatus. A waste liquid filter unit filters the waste liquid in that tank to purify the waste liquid into fresh water. A fresh water reservoir tank reserves the fresh water obtained by filtering the waste liquid by the waste liquid filter unit. A pure water producing unit purifies the fresh water reserved in the fresh water reservoir tank into pure water, and a temperature control unit controls the pure water obtained by purifying the fresh water by the pure water purifying unit to a predetermined temperature. A bubble water seal type pump sucks at least bubbles generated in the waste liquid filter unit, and a sealing water reservoir tank reserves the bubbles sucked by the bubble water seal type pump as a waste liquid.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to a waste liquid treating apparatus forpurifying a waste liquid discharged by a processing apparatus.

Description of the Related Art

A wafer formed with a plurality of devices such as integrated circuits(ICs) and large-scale integrated circuits (LSIs) on a surface in thestate of being partitioned by a plurality of streets is ground on theback side by a grinding apparatus to be formed into a predeterminedthickness and is thereafter divided by a dicing apparatus intoindividual device chips, which are used for electric apparatuses such asmobile phones and personal computers.

A processing apparatus such as the grinding apparatus and the dicingapparatus uses a large amount of pure water as processing water. Directdisposal of the processing water used for processing is uneconomical. Inview of this, a waste liquid treating apparatus for purifying the usedprocessing waste liquid discharged from the processing apparatus, toregenerate the processing water, and recirculating the regeneratedprocessing water to reuse the processing water has been proposed by thepresent applicant (see Japanese Patent Laid-open No. 2009-190128).

SUMMARY OF THE INVENTION

Incidentally, in constructing a processing water circulation systemusing a processing apparatus and a waste liquid treating apparatus, inorder to restrain deposition of cutting chips and the like onto theworkpiece to be processed by a processing unit of the processingapparatus, surfactant may be mixed into processing water introduced intothe processing apparatus. When this surfactant is used by being mixedinto the processing water, bubbles may be generated in the waste liquidtreating apparatus and may leak to the exterior, making it impossible todirectly continue the operation.

It is accordingly an object of the present invention to provide a wasteliquid treating apparatus by which bubbles generated in a processingregion of a processing apparatus is prevented from leaking to theexterior.

In accordance with an aspect of the present invention, there is provideda waste liquid treating apparatus for purifying a waste liquiddischarged from a processing apparatus, the waste liquid treatingapparatus including a waste liquid accommodating tank that accommodatesa waste liquid discharged by the processing apparatus, a waste liquidfilter unit that filters the waste liquid in the waste liquidaccommodating tank to purify the waste liquid into fresh water, a freshwater reservoir tank that reserves the fresh water obtained by filteringthe waste liquid by the waste liquid filter unit, a pure water producingunit that purifies the fresh water reserved in the fresh water reservoirtank into pure water, a temperature control unit that controls the purewater obtained by purifying the fresh water by the pure water producingunit, to a predetermined temperature, a bubble water seal type pump thatsucks at least bubbles generated in the waste liquid filter unit, and asealing water reservoir tank that reserves the bubbles sucked by thebubble water seal type pump as a waste liquid. In the waste liquidtreating apparatus, the waste liquid reserved in the sealing waterreservoir tank is filtered by the waste liquid filter unit together withthe waste liquid in the waste liquid accommodating tank, and the purewater controlled to the predetermined temperature is supplied to theprocessing apparatus.

Preferably, the waste liquid accommodating tank and the sealing waterreservoir tank are disposed adjacent to each other through a weir, thewaste liquid reserved in the sealing water reservoir tank flows over theweir into the waste liquid accommodating tank side, the waste liquidreserved in the sealing water reservoir tank is supplied through thetemperature control unit to the bubble water seal type pump, to be usedfor cooling and operation of the bubble water seal type pump.

Preferably, the waste liquid treating apparatus further includes a spraywater seal type pump that sucks a spray in a processing region where theprocessing unit is disposed, and the spray sucked by the spray waterseal type pump is supplied to the sealing water reservoir tank.

According to the present invention, the waste liquid reserved in thesealing water reservoir tank is filtered by the waste liquid filter unittogether with the waste liquid in the waste liquid accommodating tank,and the pure water controlled to the predetermined temperature issupplied to the processing apparatus. Therefore, even when surfactant ismixed into processing water and bubbles are generated upon operation ofthe waste liquid treating apparatus, the problem of leakage of thebubbles to the exterior of the waste liquid treating apparatus issolved.

The above and other objects, features and advantages of the presentinvention and the manner of realizing them will become more apparent,and the invention itself will best be understood from a study of thefollowing description and appended claims with reference to the attacheddrawings showing a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view depicting an outline of a processing watercirculation system including a processing apparatus and a waste liquidtreating apparatus;

FIG. 2 is a perspective view depicting an outline of the inside of thewaste liquid treating apparatus by detaching a cover member; and

FIG. 3 is a perspective view depicting a state in which the waste liquidtreating apparatus has been decomposed into its components, forexplaining the operation of a circulation system.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A waste liquid treating apparatus according to an embodiment of thepresent invention will be described in detail below, referring to theattached drawings. FIG. 1 illustrates an example of a processing watercirculation system which includes a waste liquid treating apparatus 1configured based on the present embodiment and a processing apparatus N.The processing apparatus N is, for example, a dicing apparatus, whichincludes a cutting unit N1 as a processing unit. A workpiece, forexample, a semiconductor wafer (not illustrated), held by a chuck tableN3 is conveyed to a processing region N2 located in the directionindicated by an arrow X1 and is cut by the cutting unit N1. At the timeof cutting the wafer in the processing region N2, processing water issupplied from the cutting unit N1 to a part to be cut, the processingwater containing cutting chips or the like flows as a waste liquid, andthe waste liquid is discharged through a waste liquid discharge port N4.The waste liquid discharged through the waste liquid discharge port N4is temporarily recovered and reserved in a waste liquid sump 20 througha pipe 101. The waste liquid reserved in the waste liquid sump 20 issent to the waste liquid treating apparatus 1 through a waste liquiddischarge passage 102 by a feed pump 22 provided in the waste liquidsump 20, is purified and regenerated into pure water in the waste liquidtreating apparatus 1, and the pure water is supplied through aprocessing water supply passage 105 to the processing apparatus N, to bereused.

In the present embodiment, in addition to the above-mentionedconfiguration, a bubble water seal type pump 9 which sucks bubblesgenerated in a waste liquid filter unit 4 is provided. In the processingregion N2 of the processing apparatus N, a spray suction port N5fronting the processing region N2 is installed, and a spray ofprocessing water that is supplied from the cutting unit N1 to the partto be cut and that is atomized is sucked in the direction indicated byan arrow R1 via the spray suction port N5. The spray sucked through thespray suction port N5 is discharged via a spray discharge port N6 and issent to the waste liquid treating apparatus 1 through a spray dischargepassage 104. The spray sent to the waste liquid treating apparatus 1 isrecovered and reserved as a waste liquid, is used for operation of aspray water seal type pump to be described later, and is purified intopure water by the waste liquid treating apparatus 1, the pure waterbeing supplied to the processing apparatus N and being reused.

FIG. 2 is a perspective view depicting a general outline of the wasteliquid treating apparatus 1 according to the present embodiment andillustrates a state in which a cover member 1 a covering the whole ofthe waste liquid treating apparatus 1 at normal times has been detachedto the upper side and pipes for communication between the components areomitted as required. FIG. 3 depicts, in a decomposed state, the wasteliquid treating apparatus 1 illustrated in FIG. 2, for explaining indetail the processing water circulation system depicted in FIG. 1; FIG.3 illustrates the pipes for communication between the components thathave been omitted in FIG. 2.

As illustrated in FIG. 2, the waste liquid treating apparatus 1 includesa waste liquid accommodating tank 2 a that temporarily accommodates thewaste liquid discharged by the processing apparatus N, the bubble waterseal type pump 9 that sucks at least bubbles generated in the wasteliquid filter unit 4, a sealing water reservoir tank 2 b that recoversthe bubbles sucked by the bubble water seal type pump 9 and reserves thebubbles as a waste liquid, the waste liquid filter unit 4 that filtersthe waste liquid in the waste liquid accommodating tank 2 a and thewaste liquid reserved in the sealing water reservoir tank 2 b, to purifythe waste liquids into fresh water, a fresh water reservoir tank 5 thatreserves the fresh water obtained by filtering the waste liquid by thewaste liquid filter unit 4, a pure water producing unit 6 that purifiesthe fresh water reserved in the fresh water reservoir tank 5 into purewater, and a temperature control unit 8 that controls the pure waterobtained by purifying the fresh water by the pure water producing unit 6to a predetermined temperature.

In the present embodiment, the waste liquid accommodating tank 2 a andthe sealing water reservoir tank 2 b are adjacent to each other througha weir 2 c to integrally constitute a reservoir tank 2. The waste liquidreserved in the sealing water reservoir tank 2 b can flow over the weir2 c into the waste liquid accommodating tank 2 a side. When the amountof the waste liquid reserved in the sealing water reservoir tank 2 b isincreased, the waste liquid flows over the weir 2 c out to the wasteliquid accommodating tank 2 a side and is supplied to the waste liquidfilter unit 4. The waste liquid reserved in the sealing water reservoirtank 2 b is sent through the temperature control unit 8 to the bubblewater seal type pump 9, to cool the bubble water seal type pump 9 and tobe used as sealing water for operation of the bubble water seal typepump 9.

The waste liquid treating apparatus 1 includes a control unit 10 thathas a display monitor 10 a on the whole surface of the cover member 1 aand controls each of operating sections of the waste liquid treatingapparatus 1 to be described later. The display monitor 10 a has a touchpanel function and is used for displaying processing conditions andprocessing status and for inputting the processing conditions, and thelike. Referring to FIG. 3 also, an operation of the waste liquidtreating apparatus 1 according to the present embodiment will bedescribed below.

When an operator instructs the control unit (not illustrated) of theprocessing apparatus N and the control unit 10 of the waste liquidtreating apparatus 1 to start operations, operations of the processingunit N and the waste liquid treating apparatus 1 are thereby started.When the operation of the processing apparatus N is started and cuttingof the wafer is started, processing water is supplied to the part to beprocessed, from the cutting unit N1 in the processing region N2, asdescribed above, then, the processing water becomes a waste liquidcontaining cutting chips, and the waste liquid is discharged via thewaste liquid discharge port N4. The waste liquid discharged via thewaste liquid discharge port N4 is temporarily reserved in the wasteliquid sump 20.

The waste liquid reserved in the waste liquid sump 20 is sent throughthe waste liquid discharge passage 102 to the waste liquid treatingapparatus 1, by an operation of the feed pump 22. The waste liquid sentto the waste liquid treating apparatus 1 is accommodated in the wasteliquid accommodating tank 2 a. The waste liquid accommodated in thewaste liquid accommodating tank 2 a is sent through a pipe 106 to thewaste liquid filter unit 4, by an operation of a feed pump 2 e. Notethat, when the amount of the waste liquid in the waste liquidaccommodating tank 2 a becomes small, the waste liquid is introducedfrom the waste liquid sump 20, as required. The waste liquid filter unit4 includes a first filter 4 a and a second filter 4 b, which aredisposed on a fresh water receiving pan 4 c.

A solenoid on-off valve 42 is disposed on the pipe 106 that connects thefeed pump 2 e, the first filter 4 a, and the second filter 4 b. Asillustrated in the drawing, in the case where the solenoid on-off valve42 is in an OFF state and is biased to the left side (1 side) by aspring, the waste liquid sent by the feed pump 2 e is led to the firstfilter 4 a, and, when the solenoid on-off valve 42 is energized (ON) andis biased to the right side (0 side), the waste liquid sent by the feedpump 2 e is led to the second filter 4 b. The waste liquid led to thefirst filter 4 a or the second filter 4 b is filtered by removal of thecutting chips and the like mixed in the waste liquid, to be purifiedinto fresh water, which flows out to the fresh water receiving pan 4 c.

Though omitted from illustration, a pressure gauge connected to thecontrol unit 10 is connected onto the pipe 106, and the pressure gaugemonitors the pressure inside the pipe 106. When the filtration of thewaste liquid is carried out continuously by the filter on one side,cutting chips and the like deposit on the filter to cause clogging,whereby the pressure of the pressure gauge is raised. Upon detectingthis, the control unit 10 determines that the filter on the one side inconnection is not functioning sufficiently, displays on the displaymonitor 10 a of the control unit 10 an instruction for replacement ofthe filter on the one side, and changes the position of the solenoidon-off valve 42, whereby the flow of the waste liquid can be changedover to the filter on the other side that is not clogged. As a result,in response to the instruction from the control unit 10, the operatorcan replace the filter on the side on which clogging has occurred.

The fresh water filtered by the first filter 4 a or the second filter 4b and having flowed out into the fresh water receiving pan 4 c isdischarged to and reserved in the fresh water reservoir tank 5 through apipe 107 connected to a discharge hole 4 d formed in the fresh waterreceiving pan 4 c. The fresh water reserved in the fresh water reservoirtank 5 is sent by a feed pump 5 a, as required, and is sent through apipe 108 to a pure water producing unit 6.

The pure water producing unit 6 in the present embodiment includes asupport base 6 a, an ultraviolet (UV) irradiation unit 6 b erected onthe depth side of the support base 6 a, a first ion exchange unit 6 cand a second ion exchange unit 6 d that are disposed on the operator'sside and incorporate an ion exchange resin, a precision filter 6 edisposed adjacent to the UV irradiation unit 6 b, and a partition plate6 f that partitions the UV irradiation unit 6 b and the precision filter6 e side and the first ion exchange unit 6 c and the second ion exchangeunit 6 d side from each other.

The fresh water sent by the feed pump 5 a and sent through the pipe 108is first introduced into the UV irradiation unit 6 b, and the introducedfresh water is irradiated with UV rays, to thereby be sterilized. Thefresh water subjected to the sterilizing treatment in the UV irradiationunit 6 b is introduced into the first ion exchange unit 6 c or thesecond ion exchange unit 6 d through a pipe 109. A solenoid on-off valve62 is disposed in the pipe 109. In the case where the solenoid on-offvalve 62 is in an OFF state and is biased to the left side (1 side) by aspring, the fresh water sent by the feed pump 5 a is led to the firstion exchange unit 6 c, and, when the solenoid on-off valve 62 isenergized (ON) and is biased to the right side (0 side), the fresh watersent by the feed pump 5 a is led to the second ion exchange unit 6 d.

The fresh water introduced into the first ion exchange unit 6 c or thesecond ion exchange unit 6 d is subjected to ion exchange, to thereby bepurified into pure water. The pure water thus obtained by ion exchangeof the fresh water may contain a fine substance such as resin chips ofthe ion exchange resin constituting the first ion exchange unit 6 c andthe second ion exchange unit 6 d mixed therein. In view of this, in thepresent embodiment, the pure water obtained through ion exchange of thefresh water by the first ion exchange unit 6 c and the second ionexchange unit 6 d as described above is introduced into the precisionfilter 6 e through a pipe 110, and the fine substance such as resinchips of the ion exchange resin mixed in the pure water is trapped bythe precision filter 6 e, whereby the pure water is put into a state ofbeing usable as processing water.

An unillustrated pressure detection unit for detecting the pressure ofthe pure water sent from the first ion exchange unit 6 c or the secondion exchange unit 6 d to the precision filter 6 e is disposed in thepipe 110, and a detection signal of the pressure detection unit is sentto the control unit 10. When the detection signal from the pressuredetection unit reaches or exceeds a predetermined value, the controlunit 10 determines that a fine substance such as resin chips hasdeposited in the precision filter 6 e and the function as a filter hasbeen lost and displays it on the display monitor 10 a provided in thecontrol unit 10, to permit the operator to replace the precision filter.Further, though omitted from the illustration, in parallel to theabove-mentioned pressure detection unit, a resistivity meter fordetecting the resistivity of the pure water flowing in the pipe 110 isdisposed. As a result, the state of the ion exchange resin of each ofthe ion exchange units can be detected, and an instruction forreplacement of the ion exchange resin can be given to the operator.

The processing water purified into pure water by the pure waterproducing unit 6 is introduced into a heat exchanger 8 b constitutingthe temperature control unit 8 through a pipe 111, by an operation of apump P disposed on the processing water supply passage 105. Thetemperature control unit 8 includes a liquid cooler 8 a for coolingliquid and circulation passages 81 and 82 for circulating the liquidcooled by the liquid cooler 8 a (cooling liquid), and the heat exchanger8 b is disposed on the circulation passages 81 and 82. The processingwater introduced into the heat exchanger 8 b is controlled to atemperature suitable for use in the processing apparatus N, on the orderof 22° C. to 23° C., by the cooling liquid circulated in the circulationpassages 81 and 82, and is supplied to the processing apparatus N viathe processing water supply passage 105.

In the waste liquid treating apparatus 1 of the present embodiment, thebubble water seal type pump 9 configured to suck bubbles generated inthe waste liquid filter unit 4 is provided. In constituting theprocessing water circulation system including the processing apparatus Nusing the processing water, as depicted in FIG. 3, in order to restrainadhesion of cutting chips and the like onto the workpiece, a surfactantsupply unit L including a surfactant reservoir tank L1 and a quantitycontrol valve L2 is disposed on the processing water supply passage 105for supplying processing water to the processing apparatus N, and atrace amount of surfactant is introduced into the processing water.

As described above, when the surfactant is introduced into theprocessing water and the waste liquid treating apparatus 1 is operated,bubbles are liable to be generated in the inside of the waste liquidtreating apparatus 1, particularly in the waste liquid filter unit 4that performs filtration by passing the waste liquid through a finefilter, and the problem of leakage of the bubbles to the exterior isgenerated. The bubble water seal type pump 9 in the present embodimentis provided for coping with this problem, and its operation will bedescribed below.

A bubble suction port 24 for sucking the generated bubbles is disposedin the fresh water receiving pan 4 c constituting the waste liquidfilter unit 4. As a part of the fresh water receiving pan 4 c isdepicted in an enlarged form on the upper side in FIG. 3, the bubblesuction port 24 is disposed at a position slightly higher than theposition reached by a liquid surface Wa of the fresh water W havingflowed out into the fresh water receiving pan 4 c, such as to makecontact with the bubbles denoted by B in FIG. 3 and generated on theliquid surface Wa, and is, for example, in what is generally called ahorn-like shape with an opening flared out on the lower surface side.

The bubble water seal type pump 9 includes a suction hole 9 a and adischarge hole 9 b. Into the suction hole 9 a of the bubble water sealtype pump 9, the bubbles sucked from the fresh water receiving pan 4 cthrough the bubble suction port 24 and a pipe 115 and the waste liquidreserved in the above-mentioned sealing water reservoir tank 2 b areintroduced. The waste liquid introduced into the bubble water seal typepump 9 is introduced through the piping 112, the heat exchanger 8 cconstituting the temperature control unit 8, and a pipe 116 disposed bybeing branched from the pipe 113, by an operation of the feed pump 2 ddisposed in the sealing water reservoir tank 2 b, and, as in theabove-mentioned heat exchanger 8 b, in a state of being controlled to apredetermined temperature, for example, on the order of 22° C. to 23°C., is used for cooling the bubble water seal type pump 9 and as sealingwater for operation of the bubble water seal type pump 9.

Note that in the present embodiment, the bubble suction port 24 isdisposed not only in the fresh water receiving pan 4 c of theabove-mentioned waste liquid filter unit 4 but also in the waste liquidsump 20, the waste liquid accommodating tank 2 a, the sealing waterreservoir tank 2 b, and the fresh water reservoir tank 5. The bubblesuction port 24 disposed in the waste liquid sump 20 is connectedthrough a pipe 103, the bubble suction port 24 disposed in the wasteliquid accommodating tank 2 a is connected through a pipe 117, thebubble suction port 24 disposed in the sealing water reservoir tank 2 bis connected through a pipe 118, and the bubble suction port 24 disposedin the fresh water reservoir tank 5 is connected through a pipe 119, tothe bubble suction hole 9 a of the bubble water seal type pump 9.

When the bubbles are sucked into the bubble water seal type pump 9through the bubble suction port 24, each pipe, and the bubble suctionhole 9 a, the component of the bubbles is absorbed as liquid into thewaste liquid used as sealing water for the bubble water seal type pump9, is discharged together with the waste liquid through the dischargehole 9 b of the bubble water seal type pump 9, and is returned through apipe 120 to the sealing water reservoir tank 2 b, to be reserved. Thecomponent of the bubbles is reserved in the sealing water reservoir tank2 b together with the waste liquid having been used as sealing water asdescribed above; in the case where its amount exceeds a predeterminedamount, the waste liquid flows over the weir 2 c into the waste liquidaccommodating tank 2 a side, and, as described above, the waste liquidaccommodated in the waste liquid accommodating tank 2 a is sequentiallyfiltered, to be purified into pure water, as described above. Note thatit is not essential to dispose the bubble suction ports 24 in all of thewaste liquid sump 20, the waste liquid accommodating tank 2 a, thesealing water reservoir tank 2 b, and the fresh water reservoir tank 5,and the bubble suction ports 24 may selectively be disposed, asrequired, according to the bubble generation status.

In the present embodiment, with the bubble water seal type pump 9provided as described above, the bubbles generated from the waste liquidare securely recovered together with the waste liquid, and the problemof leakage of the bubbles generated from the waste liquid to theexterior is solved. In addition, the recovered waste liquid isrepeatedly used as sealing water for the bubble water seal type pump 9for recovering the bubbles and is sequentially purified into pure water,to be reused as processing water.

In the present embodiment, further, a spray water seal type pump 3 thatsucks a spray together with air in the processing region N2 where thecutting unit N1 of the processing apparatus N is disposed may beprovided. The spray water seal type pump 3 includes a suction hole 3 aand a discharge hole 3 b. Into the suction hole 3 a of the spray waterseal type pump 3, the spray sucked from the processing region N2 of theprocessing apparatus N and the waste liquid reserved in the sealingwater reservoir tank 2 b are introduced, through a spray dischargepassage 104. The waste liquid reserved in the sealing water reservoirtank 2 b is introduced through a pipe 112, a heat exchanger 8 cconstituting the temperature control unit 8, and a pipe 113, by anoperation of the feed pump 2 d disposed in the sealing water reservoirtank 2 b, and is used as sealing water (indicated by alternate long andshort dash lines) for operation of the spray water seal type pump 3. Theheat exchanger 8 c is disposed on circulation passages 83 and 84 forcirculating a liquid cooled in the liquid cooling section 8 a (coolingliquid). The waste liquid introduced into the heat exchanger 8 c iscontrolled to a temperature on the order of 22° C. to 23° C. by thecooling liquid circulated in the circulation passages 83 and 84 and issupplied through the pipe 113 into the spray water seal type pump 3. Thespray introduced into the spray water seal type pump 3 is cooled by thewaste liquid introduced into the spray water seal type pump 3 andsupplied as sealing water, is separated from air introduced into thesuction hole 3 a, joins the waste liquid used as sealing water foroperation of the spray water seal type pump 3, is discharged through thedischarge hole 3 b, and is returned through a pipe 114 to the sealingwater reservoir tank 2 b, to be reserved.

The waste liquid sent to and reserved in the sealing water reservoirtank 2 b is sent to the spray water seal type pump 3 again, is used foroperation of the spray water seal type pump 3, and is circulated betweenthe sealing water reservoir tank 2 b and the spray water seal type pump3. Here, the waste liquid returned to and reserved in the sealing waterreservoir tank 2 b contains the waste liquid recovered by separating thespray sucked from the processing region N2 of the processing apparatusN, and, therefore, is gradually increased in amount. In the presentembodiment, the waste liquid accommodating tank 2 a and the sealingwater reservoir tank 2 b are disposed adjacent to each other through theweir 2 c to constitute the reservoir tank 2; in the case where the wasteliquid reserved in the sealing water reservoir tank 2 b is increased inamount by the waste liquid separated from the spray and exceeds apredetermined amount, the waste liquid can flow over the weir 2 c intothe waste liquid accommodating tank 2 a, and, as described above, thewaste liquid accommodated in the waste liquid accommodating tank 2 a issequentially purified as processing water. In the present embodiment,with the above configuration provided, the spray is securely recoveredas the waste liquid, and the recovered waste liquid is repeatedly usedas sealing water for recovering the spray as the waste liquid and ispurified into pure water, to be reused as processing water, so that theproblem of being uneconomical is solved.

According to the present invention, the above-described embodiment isnot limitative, and various modifications are provided. For example,while an example in which the waste liquid treating apparatus 1 of thepresent embodiment is applied to a dicing apparatus including a cuttingunit including a cutting blade as a processing unit has been presentedin the above embodiment, the present invention is not limited to this.The present invention is also applicable to other processing apparatusesfor processing a workpiece by use of processing water, for example, to agrinding apparatus and a polishing apparatus.

In the above embodiment, a configuration in which the waste liquidaccommodating tank 2 a and the sealing water reservoir tank 2 b arecombined integrally through the weir 2 c to form the reservoir tank 2and the waste liquid spilling over from the sealing water reservoir tank2 b flows out via the weir 2 c has been adopted, but this is notlimitative of the present invention. The waste liquid accommodating tank2 a and the sealing water reservoir tank 2 b may be formed of separatetanks, and, in the case where the waste liquid flowing into the sealingwater reservoir tank 2 b is increased in amount, the waste liquid may besent to the waste liquid accommodating tank 2 a by use of an appropriatepump.

In the above-mentioned embodiment, an example in which one processingregion N2 is formed for one processing apparatus N and only one spraywater seal type pump 3 is disposed correspondingly to the processingregion N2 has been presented. However, for example, in the case ofconstructing a processing water circulation system in which a pluralityof processing regions N2 are present, the spray water seal type pump 3may be disposed according to the number of the processing regions N2.

The present invention is not limited to the details of the abovedescribed preferred embodiment. The scope of the invention is defined bythe appended claims and all changes and modifications as fall within theequivalence of the scope of the claims are therefore to be embraced bythe invention.

What is claimed is:
 1. A waste liquid treating apparatus for purifying awaste liquid discharged from a processing apparatus, the waste liquidtreating apparatus comprising: a waste liquid accommodating tank thataccommodates the waste liquid discharged by the processing apparatus; awaste liquid filter unit that filters the waste liquid in the wasteliquid accommodating tank to purify the waste liquid into fresh water; afresh water reservoir tank that reserves the fresh water obtained byfiltering the waste liquid by the waste liquid filter unit; a pure waterproducing unit that purifies the fresh water reserved in the fresh waterreservoir tank into pure water; a temperature control unit that controlsthe pure water obtained by purifying the fresh water by the pure waterproducing unit to a predetermined temperature; a bubble water seal typepump that sucks at least bubbles generated in the waste liquid filterunit; and a sealing water reservoir tank that reserves a liquid portionof the bubbles sucked by the bubble water seal type pump as a wasteliquid, wherein the waste liquid reserved in the sealing water reservoirtank is filtered by the waste liquid filter unit together with the wasteliquid in the waste liquid accommodating tank, and the pure watercontrolled to the predetermined temperature is supplied to theprocessing apparatus; wherein the waste liquid filter unit includes afresh water receiving pan and a bubble suction port disposed in saidfresh water receiving pan, the bubble suction port being configured tosuck bubbles from liquid in the fresh water receiving pan.
 2. The wasteliquid treating apparatus according to claim 1, wherein the waste liquidaccommodating tank and the sealing water reservoir tank are disposedadjacent to each other through a weir, the waste liquid reserved in thesealing water reservoir tank flows over the weir into the waste liquidaccommodating tank side, and the waste liquid reserved in the sealingwater reservoir tank is supplied through the temperature control unit tothe bubble water seal type pump, to be used for cooling and operation ofthe bubble water seal type pump.
 3. The waste liquid treating apparatusaccording to claim 1, further comprising: a spray water seal type pumpthat sucks a spray in a processing region where a processing unit isdisposed, wherein the spray sucked by the spray water seal type pump issupplied to the sealing water reservoir tank.
 4. The waste liquidtreating apparatus according to claim 1, further comprising a controlunit connected to a pipe connected between the sealing water reservoirtank and the waste liquid filter unit, wherein said control unitmonitors a pressure inside the pipe.
 5. The waste liquid treatingapparatus according to claim 4, wherein said control unit includes adisplay monitor.